Use of a hapten specific anti-dansyl antibody for the localization of ribosomal proteins by immuno electron microscopy

The fluorescent reagent dansyl chloride has been used as an immunological marker for the electron microscopic localization of ribosomal proteins on the surface of 50S ribosomal subunits. The proteins BstL1 from Bacillus stearothermophilus and EcoL1 from Escherichia coli were dansylated to various degrees and reconstituted into the L1-deficient E. coli 50S subunits from mutant MV17-10. Using antibodies specific to dansyl chloride, both proteins were mapped at the lateral protuberance near the peptidyl transferase center.